This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. To facilitate and accelerate research in Bariatric Surgery, the National Institute of Diabetes &Digestive, and Kidney Diseases (NIDDK) established the Longitudinal Assessment of Bariatric Surgery consortium (LABS). The LABS research project, as originally conceived, focused only on adult subjects undergoing bariatric surgery. However, an ancillary studies mechanism was also established to support other related research projects. Teen-LABS is one such related project. The primary goal of this observational Teen-LABS study is to collect baseline characteristics and postoperative outcomes of adolescents who are undergoing bariatric surgery in an effort to assess safety and efficacy of bariatric surgery. By mirroring LABS data collection, the Teen-LABS study will also allow us to estimate the relative merits of early surgery compared to delayed surgery for extremely obese youth. This comparison will lead to a better understanding of the plasticity of important medical and psychosocial obesity-related comorbidities. Moreover, this study will provide critical scientific information to inform clinical decision-making regarding appropriate timing of bariatric surgery. Severe obesity in adolescence is associated with medical and psychosocial impairments which may be more effectively treated with surgery during adolescence rather than later in adulthood. Specific Aim 1: To determine whether health significantly differs between adolescents and adults seeking bariatric surgery and thereby determine whether there are potential age-related health benefits in performing bariatric surgery earlier rather than later in the lifetime. Specific Aim 2: To identify early (30 day) and intermediate term (1-2 year) health risks for adolescents and adults undergoing bariatric surgery. Specific Aim 3: To document the psychosocial status of adolescents and adults with extreme obesity before bariatric surgery and 1 and 2 years after surgery. Psychosocial status will be examined in three major domains: depressive symptoms, eating behaviors, and quality of life. Specific Aim 4: To obtain and store biospecimens (serum, plasma, whole blood, and liver tissue) for research related to the aims of this study, and for future use by this consortium and ancillary studies for research into the pathophysiology and genetics of obesity and obesity related issues. Bariatric surgery is effective in treating extreme obesity in adults, and is most commonly used in the 5th decade of life. As more adolescents develop extreme obesity and seek bariatric surgery, our long term goal is to elucidate the health benefits and risks of surgical weight loss for adolescents. Our central hypothesis is that severe obesity in adolescence is associated with medical and psychosocial impairments which may be more effectively treated with surgery during adolescence rather than later in adulthood.